An agent is required to simulate the movement and behavior of a user in a Virtual Environment (VE) such as a virtual training system or a computer game. Such an agent can not only simply project virtual space from the viewpoint of a user, but also provides realism which provides the user with the impression of actually existing in the virtual space. Accordingly, there have been proposals in which virtual sensors are provided such that an agent can experience senses of vision, audition and touch.
In the conventional system, however, interaction between the agent and various physical objects was taken into consideration, and a method in which the agent autonomously recognizes objects is not taken into consideration. Therefore, the conventional system has difficulty implementing visible objects from the viewpoint of the agent and requires a long time to display visible objects on a screen. There was proposed a scheme which previously defined objects which were recognized by an agent, in which case there is the inconvenience of the definitions having to be frequently changed when objects are added or deleted.